A veterinary technician notes that a dog’s leukocyte count before surgery was 18,645. Two days after the surgery, the patient had a leukocyte count of 8,968. What is the difference in the leukocyte counts?

A veterinary technician notes that a dog’s leukocyte count before surgery was 18,645. Two days after the surgery, the patient had a leukocyte count of 8,968. What is the difference in the leukocyte counts?

• A. 9577
• B. 1845
• C. 6977
• D. 9677

Answer: (D)

Finding how much a value has changed means subtracting the later value from the earlier one. Here, the leukocyte count goes from 18,645 before surgery to 8,968 after surgery, so the change is 18,645 − 8,968. Subtracting 8,000 gives 10,645, and subtracting the remaining 968 gives 9,677. The leukocyte count decreased by 9,677 cells (per microliter).

Finding how much a value has changed means subtracting the later value from the earlier one. Here, the leukocyte count goes from 18,645 before surgery to 8,968 after surgery, so the change is 18,645 − 8,968. Subtracting 8,000 gives 10,645, and subtracting the remaining 968 gives 9,677. The leukocyte count decreased by 9,677 cells (per microliter).